well I see your using Firefox,and I'm glad you used a screen shot to tell us what the issue is so that helps,but I have never seen that before.Sorry,but that is an unknown thing to me.It is most likely a rare,and odd glitch though.I can't say for sure,but I believe that may be the problem most likely.Sorry if I couldn't help you.
Also while I know this is a little off topic I noticed in that screen shot there was a button on one of your tool bars saying Armorgames.What is the purpose of that button,and if its an add-on then what is the add-on's name?If this has been happening for a week then there may be a glitch within one of your add-on's that could cause something within the site to become incompatible with the browser.
Yeah only AG.And the AG toolbar thing is a quicklink to help you if you forgot the name or if you just want to go to AG fast.That is the purpose of Firefox.